Elise Mertens dropped just four games as she eased past Andrea Petkovic at the Mallorca Open, with Sofia Kenin and Belinda Bencic also making it through to round two.
Fourth seed Mertens had a first-serve percentage of just 47, though it did not hamper her as she saw off Petkovic 6-2 6-2, converting match point at the third time of asking.
"I just felt good today and for my first match on grass," Mertens said in quotes published on the WTA's website.
"I was a little bit nervous to get the win, but I'm really happy to get it."
Kenin, who beat Serena Williams at the French Open but was knocked out by eventual champion Ashleigh Barty in the last 16, defeated Mertens' Belgian compatriot Kirsten Flipkens 6-2 6-3.
Bencic, the third seed in Mallorca, secured a 7-5 6-4 success over Rebecca Peterson.